1. Field of the Invention
The present invention relates to an electronic part having a flat air-bridge interconnection and a method of manufacturing such an electronic part.
2. Description of Related Art
A conventional electronic part having an air-bridge interconnection has a structure in which an air-bridge interconnection body 14b has recessed shoulder portions 14c formed by the manufacturing method thereof at upper portions of posts 14a, as shown in FIG. 11.
The method of manufacturing such electronic parts having a conventional air-bridge interconnection will be described below with reference to FIGS. 7 to 11.
First as shown in FIG. 7, post base electrodes 12a and 12b and a lower interconnection 12c between the post base electrodes 12a and 12b are formed on a substrate 11. Next, a lower resist 13 is formed on the substrate 11 in such a manner that openings 13a are formed on the post base electrodes 12a and 12b and such that the lower interconnection 12c is covered with the lower resist 13.
Thereafter, a power supplying film 15 (which may for example be used to supply power in an electrolytic plating process for forming the metal film 14a, 14b discussed below in connection with FIG. 10) is formed on the lower resist 13 and on the post base electrodes 12a and 12b in the openings 13a, as shown in FIG. 8.
As shown in FIG. 9, an upper resist 16 is next formed in such a manner that an opening 16a corresponding to a predetermined length of a bridge interconnection body is formed on the power supplying film 15.
Subsequently, a metal film is formed so as to provide posts 14a and an air-bridge interconnection body 14b at the same time, as shown in FIG. 10. Thereafter, the upper resist 16, the portion of the power supplying film 15 formed on the lower resist 13, and the lower resist 13 are removed, whereby an electronic part having an air-bridge interconnection, shown in FIG. 11, is completed.
However, since the conventional electronic part having an air-bridge interconnection, shown in FIG. 11, is manufactured by providing at the same time the metal film constituting the posts 14a of the air-bridge interconnection and the metal film constituting the body 14b of the air-bridge interconnection, the shoulder portions 14c are formed in the air-bridge interconnection body 14b above the posts 14a. The shoulder portions 14c cause variations in the thickness of the interconnection and thereby cause conductor loss and deterioration in Q.